3-ethylene mercaptoles of 21-hydroxy-4-pregnene-3, 20-dione, its 17-hydroxy derivative and esters thereof



United States Patent 3-ETHYLENE MERCAPTOLES OF ZI-HYDROXY- l- PREGNENE-3,20-DINE, ITS 17-HYDROXY DE- RIVATIVE AND ESTERS THEREOF Jack W. Rails, Morton Grove, Ill., assignor, by mesne assignments, to G. D. Searle & Co., Skokie, 111., a corporation of Delaware No Drawing. Application January 13, 1955, Serial No. 481,688

7 Claims. (Cl. 260 -2395} The present invention relates to a new group of monomercaptoles of polyketo steroids and, more specifically, to 3-ethylene mercaptoles of the 21-hydroxy-4-pregnene- 3,20-diones, their 17-hydroxy derivatives and esters thereof.

The compounds which constitute my invention can be represented by the general structural formula C Hr-S wherein X is a member of the class consisting of hydrogen, benzoyl and lower alkanoyl radicals and Y is a member of the class consisting of hydrogen and hydroxyl radicals. Among the lower alkanoyl radicals which X can represent are forrnyl, acetyl, propionyl, butanoyl, pentanoyl, hexanoyl, cyclohexaneacetyl cyclopentanepropionyl, and the like.

it has been found that condensation of 21-hydr0xy-4- pregnene-3,20diones, their esters, and their 17-hydroxy derivatives with ethanedithiol under mild conditions, such as using acetic acid as a solvent and p-toluenesulfonic acid as a catalyst, permits formation of the monomercaptole. The ZO-keto group thus remains free to undergo ketonic reactions such as reduction to the carbinol on treatment with sodium borohydride. The process of formation of the mercaptole is not accompanied by rearrangement of the 4,5-double bond to the 5,6 position. After operation on the 20-keto group, the S-ethylene mercaptole group can be reconverted conveniently to a 3-keto group by treatment with mercuric chloride and cadmium carbonate in aqueous acetone.

The compounds of this invention are also valuable pharmaceutical agents. It has been found that these 3- ethylene mercaptoles inhibit the pharmacological effect of the 3-ketosteroids from which they are derived. Especially the claimed compounds antagonize the sodium retaining and hypertensive effects of desoxycorticosterone and its esters.

'l' he following examples illustrate in further detail some of the compounds which constitute the invention and methods for their synthesis. However, the invention is not to be construed as limited in spirit and in scope by the details set forth therein. It will be apparent to those skilled in the art that numerous modifications in materials and methods can be adopted without departing from the invention in spirit or in scope. In these examples quantities of materials are indicated as parts by weight.

2,144,109 Patented May 1, 1956 2 This application is a continuation-impart of my copending application, Serial No. 425,023, filed April 22, 1954.

Example 1 .The infrared absorption spectrum as determined in a potassium bromide disc shows maxima at 2.95, 5.80, 7.30, 7.92, 8.08, and 9.58 microns.

Example 2 To a solution of 11.6 parts of 17, 21-dihydroxy-4- pregnene-lalfi-ditme in 270 parts of warm acetic acid are added 2.46 parts of ethanedithiol and a solution of 2.7 parts of p-toluenesulfonic acid monohydrate in 32 parts of acetic acid. The mixture is maintained at 25 C. for an hour and then poured into water. The reaction mixture is then extracted with chloroform and the chloroform solution is washed successively with water, 5% potassium hydroxide solution and again with water. The extract is dried over anhydrous sodium sulfate, filtered and evaporated to yield 17, 21-dihydroxy-4-pregnene-3,- 20-dione 3-ethylene mercaptole as a solid. The infrared absorption spectrum shows maxima at 2.92, 5.78, and 9.52 microns.

Example 3 To a solution of 18.63 parts of 21-acetoxy-4-pregnene- 3,20-dione in 250 parts of acetic acid are added 4.63 parts of ethanedithiol and a solution of 4.6 parts of p-toluenesulfonic acid monohydrate in 15 parts of acetic acid. After minutes standing at room temperature, the crystalline precipitate is collected on a filter and washed successively with cold acetic acid and cold methanol. It is then crystallized from ethyl acetate to yield 21- acetoxy 4 pregnene 3,20 dione 3 ethylene mer-.

captole melting at about 175176 C. The compound shows no absorption maxima in the ultraviolet region from 220 to 360 millimicrons. Major infrared absorption maxirna are observed at 5.70, 5.80, 8.08, medium intensity maxima at 7.28 and 9.44 microns, and minor maxirna at 6.95, 7.08, 7.82, and 11.72 microns. specific rotation of a 1.19% solution in chloroform is +197".

Example 4 To a mixture of 41 parts of 2l-hydroxy-4pregnene- 3,20-dione in 700 parts of acetic acid and 13 parts of ethanedithiol is added a solution of 12.5 parts'of ptoluenesulfonic acid monohydrate in parts of acetic acid. The reaction mixture is maintained at 20 C. for 2 hours and then poured into water and extracted with chloroform. This extract is Washed successively with water, 5% sodium hydroxide solution and once more with Water. It is then dried over anhydrous calcium sulfate, filtered and evaporated toyield a solid residue which on recrystallization from ethyl acetate yields 21- hydroxy-4-pregnene-3,ZO-dione B-ethylene mercaptole as white needles. The infrared absorption spectrum, as determined in a potassium bromide disc, shows maxima at 2.91, 5.82, and 9.52 microns. i

The

Example A mixture of 48.3 parts of the S-cyclopentyl-propionate of 1l-desoxycorticosterone, 8.2 parts of ethanedithiol,

9 parts of p-toluenesulfonic acid monohydrate and 1000 parts of acetic acid is stirred for 5 hours and then poured The resulting suspension is extracted with The extract is washed successively with After into water. chloroform. water, 5% sodium hydroxide solution, and water.

drying over anhydrous sodium sulfate and evaporation of the solvent, one obtains as a residue 2l-(fl-cyclopentylpropionyloxy)-4-pregnene-3,20-dione 3-ethylene mercaptole which has the structural formula CHz-CH:

Hs-S

Example 6 needles. The infrared absorption spectrum shows maxima at 5.85, 7.82, 8.92, 9.52 and 13.88 microns.

I claim: 1. A compound of the structural formula CHzO-X to I --Y j CH CH 5 I T- i CHT-s wherein X is a member of the class consisting of hydrogen, benzoyl and lower alkanoyl radicals and Y is a member of the class consisting of hydrogen and hydroxyl radicals.

2. A compound of the structural formula CHzO-C O-(lower alkyl) CH -S Hrs 3. A compound of the structural formula 4 4. A compound of the structural formula CHzOH (Tl/Hp CHFS/ 5. A compound of the structural formula CHzOH CHr-S 6. A compound of the structural formula OH I 7. A compound of the structural formula l ---OH C j CHr-S References Cited in the file of this patent UNITED STATES PATENTS 2,352,568 Reichstein July 27, 1944 OTHER REFERENCES Antomucci: J. Org. Chem., October 1952, pp. 1369-74 and 1341-50. 

1. A COMPOUND OF THE STRUCTURAL FORMULA 